(1) Field of the Invention
The present invention relates to electronic musical instruments and particularly to keyboard-type instruments wherein an accompaniment may be automatically improvised by the instrument. More specifically, this invention is directed to the improvisation of a musical accompaniment wherein, in response to the selection of a basic rhythm and at least a basic note, "defined" chords which employ the basic note as the root are generated and these chords are matched to the tonality of the selected rhythm and root. Accordingly, the general objects of the present invention are to provide novel and improved apparatus and methods of such character.
(2) Description of the Prior Art
The present invention is particularly well-suited for use in key-actuated electronic musical instruments, i.e., electronic organs. Many types of such instruments are commercially available and, commensurate with advances in computer science, such instruments are becoming increasingly versatile. Thus, in recent years, the sound composition to be reproduced has been digitally synthesized and the instruments include chord recognition circuits which detect a tonality actually played and generate therefrom an accompaniment comprising filling notes commensurate with the tonality, i.e., with the root note, selected by the musician. An example of a state-of-the-art electronic organ may be seen from German Patent Specification No. 30 23 578.
The accompaniment generated by prior art electronic musical instruments, as exemplified by the above-referenced German Patent Specification, is comparatively uncomplicated and meets only limited musical requirements. As is well-known, a proficient musician often improvises on a given theme, i.e., the well-trained player is able to modify a theme in accordance with certain musical rules such that he will play "mating" chords commensurate with selected notes. In the course of such improvisation, the musician may also "solve" the "mating" chords, vary the tempi, etc. Prior art electronic musical instruments have lacked circuitry which would enable the amateur musician to simulate the effect of the improvisation of the well-trained musician.